The present invention relates to an earwax protection device for a hearing aid or another hearing apparatus, for example, a headset, having a carrier that has a sound passage opening, and a membrane that is tensioned over the sound passage opening to protect against penetrating earwax.
Hearing aids are exposed during daily use to many variable materials that can cause contamination in the hearing aids and, particularly, in the transducers of the hearing aids. Such materials are, in particular, sweat and earwax. Contaminants inside transducers, specifically the microphones, lead to high service costs, since the contaminated transducers must be cleaned and, in the worse case, even replaced due to irreparable damage.
In order to solve this problem, use is frequently made of open earwax protector systems so that the earwax cannot, for example, reach the receiver directly. However, it is not always possible for such open earwax protector systems to prevent the contamination of the receiver.
As an alternative solution, German patent application no. DE 196 40 796 A1 presents a hearing aid in which the receiver is sealed off from the eardrum by a membrane. United States patent publication no. US 2005/0018866 A1 likewise discloses an acoustically transparent contamination shield for audio transducers whereby a protective film is intended to keep solid, liquid and gaseous contaminants away from the acoustic transducer.
Since the protective membranes are very thin for acoustic reasons, they are also very susceptible to damage and destruction. Consequently, there must be a continuous check as to whether the membrane is still intact. However, the problem exists here that the sound opening over which the membrane is tensioned is generally very small, and so damage to the membrane can be perceived optically only with difficulty.
The Sonion company also markets hearing aids whose receiver output is to be protected against earwax by a membrane. The use of a pocket lamp for inspecting this membrane is proposed in an “Application Note”, “C-Barrier”, dated Jan. 10, 2005, on page 15 at www.sonion.com. When the membrane is intact, it reflects the light of the pocket lamp at the appropriate angle. But if the membrane is contaminated or damaged, the light is not reflected. However, this test method can be executed directly only for a restricted group of persons since it is relatively complicated.